class RSpec::Core::MemoizedHelpers::ThreadsafeMemoized

@private

def fetch_or_store(key) 

def fetch_or_store(key)
  @memoized.fetch(key) do # only first access pays for synchronization
    @mutex.synchronize do
      @memoized.fetch(key) { @memoized[key] = yield }
    end
  end
end

def initialize 

def initialize
  @memoized = {}
  @mutex = Support::ReentrantMutex.new
end